Clutch mechanism



Oct. 11, 1938. J. HATCHER.

CLUTCH MECHANISM Filed Aug. 21, 1936 Inventnr LLHTTLEE bilatcher BM/30M Attur'ne Patented Oct. 11, 1938 etes CLUTCH MECHANISM James L. Hate-her, United States Army, Winchester, Va.

Application August 21, 1936, Serial No. 97,134

3 Claims.

(Granted under the act of March 3, 1883, as

amended April 30, 1928; 370 O. G. 757) The invention described herein may be manufactured and. used by or for the Government for governmental purposes, without the payment to me of any royalty thereon.

This invention relates to a synchronized control gear for machine guns.

In arranging a machine gun. to fire between the propeller blades of aircraft it is customary to control the operation of a trigger motor on the gun by means of an impulse generator associated with the engine that drives the prooeller.

The purpose of this invention is to provide a. clutch in the impulse generator whereby the 2am member may be retained in a neutral position or driven from different angularly dis- ;laced positions of the driving shaft to allow for different ranges of speed of the propeller Jlades. The invention has particular applica- ;ion in connection with three blade propellers.

With the foregoing and other objects in view, .he invention resides in the novel arrangement ind combination of parts and in the details of :onstruction hereinafter described and claimed, t being understood that changes in the precise embodiment of the invention herein disclosed nay be made within the scope of what is claimed vithout departing from the spirit of the in- 'ention.

A practical embodiment of the invention is llustrated in the accompanying drawing, where- Fig. 1 is a longitudinal sectional view of a iynchro-nizing gear constructed in accordance vith the invention.

Fig. 2 is a view in elevation of the clutch.

Fig. 3 is a sectional view on the line 3-3 of ig. 1.

Referring to the drawing by characters of *eference there is shown the impulse generator If a gun control assembly including a casing 5 or mounting a shaft 6 which receives its energy from the aircraft engine and rotates at tspeed to give an impulse for each blade of he propeller. A sleeve I mounted on a reduced )art of the shaft 6 is connected thereto in any uitable manner preferably by means of a split vedge nut 8 threaded on the outer end of the haft.

The sleeve 1 is provided with spaced clutch members, each having a single claw, the inner lutch member 9 being integral with the sleeve and the outer clutch member Ill being fasened to the sleeve by a key H and retained in llace by a nut l2. The claws l3 and [4 of the respective clutch members 9 and 10 are angularly displaced a predetermined amount so that they may be employed under different conditions of propeller speed. For example, in the illus- 1 tration, the displacement is sixty degrees, the 5 clutch member 9 being arranged for synchronization when the propeller speed is between idling and 1500 R. P. M., and. the clutch member Ill being advanced 60 degrees (in a clockwise direction looking upwardly from the bottom) 10 with respect to the clutch member 9 and arranged for synchronization over a speed range from 1500 to 3000 R. P. M. With respect to a particular propeller blade, the zero shot for the high range of speeds is timed ahead of the blade and the zero shot for the low range of speeds is timed behind the blade.

A clutch member [5 constituting a driven shaft slidably mounted on the sleeve 1 is provided on its opposite ends with aligned single claws I6 and I1 adapted to be respectively engaged by the angularly displaced claws I3 and M. The sliding clutch member I5 is formed with an annular groove I8 for receiving the fork I9 of a shifting member 20 which extends through anop-ening 2| in the casing 5. A pair of springs 22-22 seated on the casing 5 and acting on. opposite ends of the shifting member normally maintain the latter in neutral position. The displacement of the shifting member to move the sliding clutch l5 into engagement with the clutch members 9 and ID of the driving sleeve 1 may be accomplished either mechanically or electrically as indicated in Patent No. 1,750,706 of March 18, 1930, and governed according to the two sets of speed ranges.

The sliding or driven clutch member I5 is formed with a cam 23 adapted to engage a roller 24 carried by a cam follower 25 mounted in the casing 5. A lever 26 engaging the follower is connected by a cable 21 with a trigger motor (not shown) which is associated with the gun. The trigger motor acts on the cable in a well known manner to normally hold the follower in the path of movement of the cam 23. The cam serves to move the follower and thereby actuate the cable 21 and the triggermotor.

I claim.

1. Means for changing the phase relation of a driving and a driven shaft including a driving shaft, a sleeve fixed on said shaft, spaced clutch members on the sleeve each having a claw, the claw of one member angularly displaced with respect to the claw of the other member, a driven shaft slidably and rotatably mounted on the sleeve between the spaced clutch members and having a claw on each end, means for shifting the driven shaft.

2. Means for changing the phase relation of a driving and a driven shaft including a driving shaft having longitudinally spaced and angularly displaced driving surfaces, a driven shaft slidably and rotatably mounted on the driving shaft between the driving surfaces and having surfaces on its opposite ends for engagement with the driving surfaces, means for shifting the driven shaft into selective engagement with the 

